A novel labeling procedure of anteiso-fatty acid-containing lipids in staphylococci for investigating the effect of penicillin on lipid release.
L-[4,5-3H]isoleucine was introduced to label anteiso-fatty acid (AIFA)-containing lipids in Staphylococcus aureus SG 511. After an overnight incubation in peptone broth in the presence of 37 kBq L-[4,5-3H]isoleucine/ml, 8.5-13% of the total radioactivity applied was found to be incorporated into the cells. 22.4-25.6% of the incorporated radioactivity was found in AIFA-containing lipids extracted by chloroform-methanol-water (2:1:0.2, v/v/v) at pH 2. The interphase contained 70-75% of the incorporated radioactivity. Lipoteichoic acid, extracted by phenol-water (80:20, w/v) contained less than 1% of the incorporated radioactivity, as measured after purification by hydrophobic interaction chromatography on octyl sepharose gel. Within 1 h after addition of 10 micrograms/ml penicillin G to exponentially growing cultures of S. aureus, that led to non-lytic death of the cells, 11.9-18.1% of the incorporated L-[4,5-3H]isoleucine label were released. Lipids containing AIFA were excreted to 5.4-8.4% of total incorporated activity; this amount represents more than 1/4 of the labeled cellular lipids.
Rozgonyi
F
F
Department of Microbiology, University Medical School, Debrecen, Hungary.
Hahn
H
H
Labischinski
H
H
Giesbrecht
P
P
D005227:Fatty Acids / Q000378:metabolism*; D007532:Isoleucine / Q000378:metabolism*; D050356:Lipid Metabolism; D008055:Lipids / Q000032:analysis; D008070:Lipopolysaccharides / Q000032:analysis; D010400:Penicillin G / Q000494:pharmacology*; D013211:Staphylococcus aureus / Q000032:analysis / Q000187:drug effects / Q000378:metabolism*; D013682:Teichoic Acids / Q000032:analysis
D005227:Fatty Acids; D008055:Lipids; D008070:Lipopolysaccharides; D013682:Teichoic Acids; D007532:Isoleucine; C009900:lipoteichoic acid; D010400:Penicillin G